When the allegation of sexual assault emerged against Virginia Lt. Gov. Justin Fairfax (D) on a conservative website late Sunday, his accuser’s name and face were thrust into the center of the state’s unfolding political scandals.

Fairfax vehemently denied the allegation, saying that the woman was lying and that he was the victim of a “smear.” The woman, meanwhile, was silent.

Then, on Wednesday, Fairfax’s accuser came forward, publicly identifying herself and describing the encounter in July 2004 during which she said Fairfax sexually assaulted her.

“What began as consensual kissing quickly turned into a sexual assault,” said Vanessa Tyson, a fellow at Stanford University and associate professor at Scripps College.

She accused Fairfax of forcing her to perform oral sex during the encounter, which took place during the Democratic National Convention in Boston.

Later Wednesday, in response to Tyson’s statement, Fairfax denied the allegation of sexual assault and Tyson’s description of what happened.

“Reading Dr. Tyson’s account is painful. I have never done anything like what she suggests,” Fairfax said in a statement. “Any review of the circumstances would support my account, because it is the truth. I take this situation very seriously and continue to believe Dr. Tyson should be treated with respect. But, I cannot agree to a description of events that simply is not true.”

The allegation has further enveloped Richmond in chaos as Gov. Ralph Northam (D) resists calls to resign over a racist photo that appeared on his medical school yearbook page and his acknowledgment that he darkened his face for a dance competition in the 1980s.

Attorney General Mark R. Herring acknowledged Wednesday that he dressed in blackface while in college, plunging the state Democratic Party into crisis as all three of its statewide officeholders are now embroiled in controversies.

Fairfax, who is next in line to be governor if Northam resigns, on Monday described the encounter as consensual, called the allegation false and threatened legal action against Tyson.

In her statement, Tyson said she decided to come forward after those remarks.

“My only motive in speaking now is to refute Mr. Fairfax’s falsehoods and aspersions of my character, and to provide what I believe is important information for Virginians to have as they make critical decisions that involve Mr. Fairfax,” she said.

But after Tyson shared her story Wednesday, U.S. Rep. Robert C. “Bobby” Scott (D-Va.), the dean of the Virginia congressional delegation, released a statement in her support.

“Allegations of sexual assault need to be taken seriously,” Scott said. “I have known Professor Tyson for approximately a decade and she is a friend. She deserves the opportunity to have her story heard.”

Rep. Jennifer Wexton (D-Va.) also voiced her support of Tyson, tweeting that she believed her.

Tyson said she met Fairfax on the first day of the 2004 Democratic National Convention and the pair soon realized they had a mutual friend. On the third day of the event, Tyson said Fairfax suggested she accompany him to his hotel room to pick up some documents.

It was in that hotel room, she says, that he began to kiss her. “Although surprised by his advance, it was not unwelcome and I kissed him back,” she said. But then, she says, he forced her to perform oral sex as she cried.

“Mr. Fairfax put his hand behind my neck and forcefully pushed my head towards his crotch,” she said. “. . . Utterly shocked and terrified, I tried to move my head away, but could not because his hand was holding down my neck and he was much stronger than me.”

“To be very clear, I did not want to engage in oral sex with Mr. Fairfax and I never gave any form of consent. Quite the opposite,” Tyson said, adding that she never spoke to Fairfax again.

Tyson said she did not talk about the encounter with Fairfax for years and suppressed the memories to focus on her academic career. She said she found it “especially degrading” in part because she regularly volunteered at a local rape crisis center at the time.

“After the assault, I suffered from both deep humiliation and shame,” she said.

Then, in October 2017, she learned about Fairfax’s campaign for lieutenant governor of Virginia, and the news “hit me like a ton of bricks,” Tyson said.

At that point, she said, she began telling close friends in Virginia about the assault. Since then, “I have never wavered in my account because I am telling the truth,” she said.

After Fairfax won his November 2017 election, Tyson reached out to The Washington Post because she said she felt an obligation to report the incident, particularly amid the #MeToo movement. Scott’s aides said Tyson told Scott of the encounter shortly after she went to The Post. It’s unclear what Scott did with the information.

The Post did not run a story at the time because it could not corroborate Tyson’s account or find similar complaints of sexual misconduct.

On Friday, amid the news that Fairfax could be elevated to governor, Tyson said, she vented her frustration on Facebook in a private post, which did not identify Fairfax by name.

On Sunday night, while she was still undecided about publicly sharing her story, her Facebook post was published by Big League Politics, the same conservative website that published the racist photo from Northam’s yearbook page.

Tyson pointed out an apparent attempt by Fairfax to discredit her at his Monday news conference by mentioning a 2007 video in which she describes her history of having been sexually assaulted. In the video, she said she was the victim of incest and molestation as a child but did not mention her allegation against Fairfax.

“This, of course, is not proof that he did not assault me. His reliance on this video to say the opposite is despicable and an offense to sexual assault survivors everywhere,” Tyson said in her statement.

In her fellowship at Stanford, Tyson’s research focuses on the politics surrounding sexual violence, according to her biography.

She has been a vocal advocate for sexual violence prevention as a founding member of the Boston Area Rape Crisis Center’s Survivor Speakers Bureau. She has a bachelor’s degree in politics from Princeton University and master’s and PhD degrees in political science from the University of Chicago.

Tyson is scheduled to speak at a symposium at Stanford on Tuesday titled “Betrayal and Courage in the Age of #MeToo.”

Jennifer Freyd, also a fellow at the Center for Advanced Study in the Behavioral Sciences at Stanford, is scheduled to speak with her. Freyd said Tyson spoke to her about the 2004 incident last fall but did not identify Fairfax.

“She’s a very open person,” Freyd said. “She shares things about herself when they’re relevant to what we’re talking about.”

More than two dozen fellows at the Center for Advanced Study in the Behavioral Sciences signed a letter Wednesday saying they were proud to call Tyson a colleague.

Tyson has hired the D.C. law firm Katz, Marshall & Banks, the same legal team that represented Christine Blasey Ford when she accused then-Supreme Court nominee Brett M. Kavanaugh of sexual misconduct.

After criticism of his aggressive response, Fairfax released a statement late Wednesday morning that struck a softer tone.

“I would like to encourage the media, my supporters and others to treat both the woman who made the allegation and my family with respect for how painful this situation can be for everyone involved,” Fairfax said.

His statement also addressed his Monday remarks about the allegation, in which he insinuated that supporters of Northam and Richmond Mayor Levar Stoney, a potential political rival, were behind the assault allegations going public.

“This has been an emotional couple of days for me and my family,” Fairfax said. “And in my remarks on Monday, I think you could hear how emotional dealing with an allegation that I know is not true has been for me.”

Fairfax has legal representation from Wilkinson Walsh Eskovitz, which represented Kavanaugh when the allegations were made against him, according to partner Rakesh Kilaru.

A spokesman for the Suffolk County district attorney’s office, which has jurisdiction over crimes in Boston, declined to say whether the office has received a complaint about Fairfax.